JP5721001B2 - Coil component and power supply device and charging device using the same - Google Patents

Description

  The present invention relates to a coil component that can be widely applied to applications that require a coil and a magnetic shield, applications that require a coil and a yoke, and the like. For example, it is suitably used in a non-contact charging system that enables charging in a non-contact state by a primary coil and a secondary coil.

  In recent years, small information communication devices have been improved in performance and functionality, and in particular, portable devices such as mobile phones, web terminals, music players, etc. are required to be used continuously for a long time. Yes. In these small information communication devices, a secondary battery such as a lithium ion battery is used as a power source. This secondary battery charging method uses a contact charging method in which charging is performed by directly contacting the electrode on the power receiving side and the electrode on the power feeding side, and transmission coils are provided on both the power feeding side and the power receiving side, and electromagnetic induction is used. There is a non-contact charging method in which charging is performed by power transmission. Since the contactless charging method does not require an electrode for directly contacting the power feeding device and the charging device, it is possible to charge different charging devices using the same power feeding device. In addition, the non-contact charging method has an advantage that the problem of electrode corrosion and the problem of poor contact between electrodes can be avoided.

  In the non-contact charging method, the magnetic flux generated in the primary coil is fed by generating an electromotive force in the secondary coil via the power feeding device and the casing of the charging device. However, since sufficient transmission efficiency cannot be obtained with this transmission coil alone, a magnetic sheet is installed on the opposite side of the transmission coil from the contact surface of the power feeding device and the charging device. In a coil component including a coil and a magnetic sheet, the magnetic sheet has the following role. The first role is a role as a magnetic shield material. When leakage magnetic flux generated during the charging operation of the non-contact charging device flows to other components such as a metal member constituting the secondary battery, these components generate heat due to eddy current. The magnetic sheet can suppress this heat generation as a magnetic shield material. The second role of the magnetic sheet is to act as a yoke member that recirculates the magnetic flux generated in the coil during charging.

  As a specific example of a coil component including a coil and a magnetic sheet, for example, Patent Document 1 discloses a charging device in which a magnetic foil body is disposed between a spiral coil and a secondary battery.

  In the non-contact charging device, it is preferable that the central axes of the primary coil and the secondary coil coincide with each other in order to increase charging efficiency. As a solution, Patent Document 2 attaches permanent magnets to the power feeding surface of the power feeding device and the back side of the charging surface of the charging device, and positions both of them by magnetic adsorption so that the central axes of the primary coil and the secondary coil coincide with each other. Disclosed is a non-contact charging adapter having attachment means. The attaching means is composed of two thin L-shaped permanent magnets combined so as to extend annularly along the outer periphery of the apparatus.

WO2007 / 080820 JP 2009-159677 A

  Positioning the primary coil and the secondary coil by magnetic attraction means as in Patent Document 2 is effective for simplifying the structure. However, Patent Document 2 does not describe the point of shielding the magnetic flux emitted from the permanent magnet. Since precision devices such as portable electronic parts use electronic circuits and magnetic memories that are easily affected by magnetic flux, it is important to shield not only the coil but also the magnetic flux from the magnetic attracting member such as a permanent magnet. .

  This invention makes it a subject to provide the coil components which improved the magnetic shielding performance with respect to a magnetic adsorption member.

The coil component of the present invention is a coil component including an annular coil, a first magnetic sheet opposed to one side in the thickness direction of the coil, and a magnetic adsorption unit, and the magnetic adsorption unit includes a coil The second magnetic sheet is disposed on one side in the thickness direction of the magnetic attracting means. With the second magnetic sheet, the shielding performance of the magnetic adsorption means can be enhanced.
The second magnetic sheet is preferably disposed in a region that does not overlap the first magnetic sheet when viewed in the thickness direction. The coil component can be reduced in height, and the magnetic flux of the magnetic adsorption member that cannot be shielded by the first magnetic sheet can be effectively shielded by the second magnetic sheet. Since the magnetic attraction means is disposed on at least one of the side surfaces of the inner and outer peripheral sides of the coil, it is possible to reduce the height of the coil component.

  The second magnetic sheet is preferably arranged with respect to the first magnetic sheet via a magnetic gap in the in-plane direction and / or thickness direction of the first magnetic sheet. Thereby, since it can suppress that a 1st magnetic sheet magnetically saturates, it can suppress that the magnetic permeability of a magnetic sheet falls, and can improve charging efficiency.

  It is preferable that the magnetic attraction means is disposed with respect to the first magnetic sheet via a magnetic gap in an in-plane direction and / or a thickness direction of the first magnetic sheet. Thereby, since it can suppress that a 1st magnetic sheet magnetically saturates, it can suppress that the magnetic permeability of a magnetic sheet falls, and can improve charging efficiency.

In the first magnetic sheet, it is preferable that a hole is formed in the central portion of the coil when viewed in the thickness direction.
By forming a hole in the center of the coil, the magnetic attracting means is arranged in the center of the coil so that the charging device and the power feeding device can be easily positioned in the central portion of the coil, and the first magnetic sheet is caused by the magnetic flux from the magnetic attracting means. Magnetic saturation can be suppressed.

  It is preferable that at least a part of the second magnetic sheet projects outward from the outer edge of the magnetic attraction means when viewed in the thickness direction. By projecting outward, the area for shielding the magnetic flux from the magnetic attracting means increases, and the shielding performance improves.

  The second magnetic sheet preferably has a refracting portion formed so as to be folded into at least a part between a side surface of the coil and the magnetic attraction means. Since the side surface of the magnetic attraction means is also shielded by the refracting portion, the shielding performance can be improved, and the second magnetic sheet having the refracting portion serves as a cup-type yoke and is interposed between the power feeding device and the charging device. The working magnetic attraction can be increased. Moreover, it can suppress that the magnetic flux from a magnetic adsorption | suction means flows to the rear surface side of a coil, and will be in the state which a 1st magnetic sheet cannot carry out magnetic saturation easily. Therefore, since the fall of the magnetic permeability of a 1st magnetic sheet can be suppressed, the function as a yoke is fully acquired and the fall of electric power transmission efficiency can be suppressed as much as possible.

  It is preferable that the magnetic attraction means has a flat front surface on the other side in the thickness direction of the coil, and the refracting portion is formed so that the tip thereof is at the same height as the front surface of the magnetic attraction means. Compared to a configuration in which the refracting part covers only from one end of the magnetic attraction means to the middle of its thickness, the above-mentioned effects of improving the shielding performance and the magnetic attraction force can be obtained, and the reduction in transmission efficiency is further suppressed. Can do.

The power feeding device of the present invention may have a structure including the coil component. The shield performance can be improved by using the coil component.
Moreover, the charging device of this invention can be set as the structure provided with the said coil components. The shield performance can be improved by using the coil component.

  According to the present invention, since the magnetic flux from the magnetic attraction means can be shielded by using not only the first magnetic sheet but also the second magnetic sheet, it is possible to provide a coil component having higher shielding performance than the conventional one. Furthermore, it is possible to provide a power feeding device and a charging device using such coil components.

It is a figure which shows embodiment of a coil component. It is a figure which shows the electric power feeder and charging device using the coil components of FIG. It is a figure which shows embodiment of another coil component. It is a figure which shows embodiment of another coil component. It is a figure which shows embodiment of another coil component. It is a disassembled perspective view which shows an example of the electric power feeder used for a non-contact charging device. It is a disassembled perspective view which shows an example of the charging device used for a non-contact charging device. It is a block diagram which shows an example of the circuit of a non-contact charging device. It is a figure which shows the electric power feeder and charging device for a comparison.

  In order to solve the above problem, the present applicant forms holes in the magnetic sheets 1c and 1d as shown in FIG. 9 and arranges the holes in a magnetic gap in the in-plane direction and / or in the thickness direction. The present invention has been conceived and applied for a structure including the magnetic attraction means 2c and 2d. With the above structure, by providing a magnetic gap between the magnetic sheets 1c and 1d and the magnetic attracting means 2c and 2d, it is possible to manufacture a contactless charging device that suppresses magnetic saturation of the magnetic sheet and has high transmission efficiency. . In the present invention, it has been studied to further improve the shielding characteristic of the magnetic flux leaking to the substrate 8c, 8d side.

  Hereinafter, embodiments of the coil component, the power feeding device, and the charging device according to the present invention will be specifically described, but the present invention is not limited thereto. Moreover, the structure demonstrated in each embodiment is applicable also in other embodiment, unless the meaning of other embodiment is impaired, In that case, the overlapping description is abbreviate | omitted suitably.

  A non-contact charging apparatus to which the present invention can be applied has a circuit configuration shown in FIG. The power feeding device 20 is a power feeding unit 21 that supplies an alternating current, a rectifier circuit 22 that is connected to the power feeding unit 21 for rectifying the alternating current into a direct current, and a direct current that is input to convert the high frequency current to a predetermined frequency. A switching circuit 23 for switching, a primary coil 201 connected to the switching circuit 23 so that a high-frequency current flows, a resonance capacitor 26 connected in parallel to the primary coil 201 so as to resonate at the same frequency as the switching circuit 23, and switching A control circuit 24 connected to the circuit 23 and a control secondary coil 25 connected to the control circuit 24 are provided. The control circuit 24 controls the operation of the switching circuit 23 based on the induced current obtained from the control secondary coil 25.

  The charging device 30 includes a secondary coil 301 that receives a magnetic flux generated from the primary coil 201, a rectifier circuit 32 connected to the secondary coil 301, a secondary battery 33 connected to the rectifier circuit 32, and a secondary battery 33. A battery control circuit 34 connected to the secondary battery 33 and a control primary coil 35 connected to the battery control circuit 34 in order to detect the storage state from the voltage of A resonance capacitor (not shown) may be connected in parallel to the secondary coil 301. The rectified current is stored in the secondary battery 33 and used for an electronic circuit, a driving member (not shown), and the like. The battery control circuit 34 passes a signal for performing optimal charging to the control primary coil 35 in accordance with the storage state of the secondary battery 33. For example, when the secondary battery 33 is fully charged, a signal of that information is supplied to the control primary coil 35 and the signal is fed to the power supply device 20 via the control secondary coil 25 that is electromagnetically coupled to the control primary coil 35. To the control circuit 24. The control circuit 24 turns off the switching circuit 23 based on the signal.

  FIG. 2 is a cross-sectional view showing the power feeding device 20 and the charging device 30 used in the non-contact charging device. A specific example of the non-contact charging device is, for example, a mobile communication terminal and its charger. The power feeding device 20 and / or the charging device 30 includes the coil component according to the present invention. The charging device also includes an electronic device body having a power receiving function such as a portable terminal. The power feeding device 20 connected to the AC power source 6 includes a circuit unit 7. The circuit unit 7 includes a rectifier circuit that rectifies an alternating current and a switching circuit that converts the rectified direct current into a high-frequency current having a predetermined frequency. The high-frequency current output from the circuit unit 7 flows through the coil 3a which is a primary coil. The coil 3a is connected to a resonance capacitor (not shown) and resonates at the same frequency as the predetermined frequency converted by the switching circuit. The power feeding device 20 may be provided with a control circuit for controlling the operation of the switching circuit.

  The charging device 30 includes a coil 3b that is a secondary coil. A resonance circuit can be configured by arranging a resonance capacitor. The coil 3b is connected to the secondary battery 4 via a rectifier circuit (not shown), and the induced current induced in the coil 3b by electromagnetic induction is rectified by the rectifier circuit, and the secondary battery 4 is charged. The

  The power feeding device 20 and the charging device 30 are accommodated in a non-magnetic housing (broken line portion) such as a resin. The housing of the power feeding device 20 has a flat power feeding surface 203, and the housing of the charging device 30 also has a flat power receiving surface 303. The non-contact charging device performs charging with the power feeding surface 203 and the power receiving surface 303 facing each other. The power feeding device and the charging device are positioned and fixed to each other using magnetic attracting means 2a and 2b such as magnets. The coils 3a and 3b are arranged inside the housing so that the winding axis thereof is perpendicular to the flat surface (the surface of the planar coil is parallel to the flat surface). On the opposite side of the flat surface of the coils 3a and 3b, first magnetic sheets 1-1a and 1-1b are respectively arranged adjacent to each other. Inside the housing, for example, substrates 8a and 8b such as resin substrates are arranged. The magnetic sheets 1-1a and 1-1b are disposed so that the main surfaces thereof overlap or cover the coils 3a and 3b between the substrates 8a and 8b on which the secondary battery 4 and the like are installed and the coils 3a and 3b. Be placed. Therefore, the magnetic flux generated by the coils 3a and 3b converges and passes through the first magnetic sheets 1-1a and 1-1b, and the magnetic sheet functions as a magnetic yoke or a magnetic shield. Further, the magnetic attracting means 2a and 2b are arranged at positions that do not overlap with the coils. The coil component including the second magnetic sheet in addition to the coil, the first magnetic sheet, and the magnetic adsorption means will be specifically described below.

  For simplification, in the power feeding device 20 and the charging device 30, the surface on the power feeding surface 203 side of each of the primary coil, the magnetic attraction means, and the magnetic sheet is referred to as “front surface”, and the surface opposite to the power feeding surface 203 is referred to as “rear surface”. " In the charging device 30, the surface on the power receiving surface 303 side of each of the secondary coil, the magnetic attraction means, and the magnetic sheet is referred to as “front surface”, and the surface opposite to the power receiving surface 303 is referred to as “rear surface”. Furthermore, the winding axis direction of each coil, the magnetic adsorption means, and the thickness direction of the magnetic sheet are simply referred to as “thickness direction”. In addition, “one side in the thickness direction” described in the claims corresponds to the “rear surface” side on the assumption that the coil component is installed in the power feeding device 20 and the charging device 30. The “in-plane direction” is a direction perpendicular to the “thickness direction”.

(First embodiment)
Fig.1 (a) is sectional drawing which shows an example of the coil component 10 of this embodiment, FIG.1 (b) is a bottom view of Fig.1 (a).
The coil component 10 of this embodiment includes an annular coil 3, a first magnetic sheet 1-1 disposed on the rear surface side of the coil, and magnetic adsorption means 2, and further, a rear surface side of the magnetic adsorption means 2. The second magnetic sheet 1-2 is disposed on the surface.
The magnetic attraction means 2 is disposed on at least one side of the inner periphery side and the outer periphery side of the coil 3. FIG. 1 shows a state in which the magnetic attracting means 2 is arranged on the inner peripheral side of the coil 3.
The second magnetic sheet 1-2 can be a magnetic sheet having the same thickness and material as the first magnetic sheet 1-1. The magnetic sheet will be described later.

The first and second magnetic sheets are arranged via a magnetic gap in the in-plane direction and / or thickness direction. Further, the magnetic attracting means is arranged with respect to the first magnetic sheet via a magnetic gap in the in-plane direction and / or the thickness direction. Since the first magnetic sheet and the second magnetic sheet and the magnetic attraction means are arranged via the magnetic gap, the magnetic saturation of the coil yoke can be suppressed and the charging efficiency can be improved.
The coil parts used in the power supply device and the charging device are required to have a low profile. When the first magnetic sheet 1-1 and the second magnetic sheet 1-2, and the first magnetic sheet 1-1 and the magnetic attraction means 2 are arranged with a magnetic gap in the thickness direction, the first magnetic sheet In order to make 1-1 a state with a low magnetic flux density that can obtain a sufficient role as a coil yoke, a sufficient magnetic gap is required, and thus it is difficult to reduce the height. Therefore, it is preferable that the second magnetic sheet 1-2 or the magnetic attraction means 2 is disposed via the first magnetic sheet 1-1 and a magnetic gap in the in-plane direction.

  The coil component has a hole formed in the central portion of the coil when the first magnetic sheet is viewed in the thickness direction, and the magnetic adsorption means and the second magnetic sheet are disposed inside the hole when viewed in the thickness direction. It is preferred that In the coil component of the above aspect, the first magnetic sheet functions as a coil yoke and a shield material for the magnetic flux generated by the coil, and the second magnetic sheet shields the magnetic flux from the magnetic adsorption means. For this reason, the magnetic flux from both the coil and the magnetic attraction means is shielded, and circuit components arranged on the rear surface side of the substrate 8 in FIG. 2 can be protected. In addition, since the magnetic flux easily flows along the second magnetic sheet, the magnetic flux emitted from the rear surface side of the magnetic attracting means 2 can easily flow around to the front surface side, so that the other power feeding device or charging device is provided. It is possible to increase the magnetic attraction force acting between the coil parts and the magnetic attraction means.

The first magnetic sheet and coil in the embodiment of FIG. 1B are annular, but various shapes such as a rectangle such as a square, a rectangle, a circle, a ring shape, an irregular shape, and a shape with irregularities formed on them. A magnetic sheet can be used.
Further, the thickness of the magnetic attraction means is preferably the same as that of the coil or thinner than that of the coil in order to reduce the height. In order to increase the magnetic attraction force, it is preferable that the front surface of the magnetic attraction means be as close as possible to the charging surface side, and considering the charging efficiency, the front surface of the magnetic attraction means is arranged at the same height as the front surface of the coil. It is preferable to do.

In FIG. 2, both the power feeding device 20 and the charging device 30 use the same coil component, but different types of coil components can be used as long as charging is possible. For example, in order to increase the charging speed, the number of turns of the coil on the power feeding device side can be made larger than that of the coil on the charging device side, or the resonance capacity can be arranged only on the power feeding device side. Further, the magnetic attraction means 2a and 2b can have different forms, for example, one can be a permanent magnet and the other can be a magnetic yoke member only.
In general, since the charging device is required to be smaller than the power supply device, the coil component arranged on the charging device side has a structure that contributes to miniaturization and low profile as much as possible.

(Second Embodiment)
FIG. 3 is a cross-sectional view of a coil component according to another embodiment.
The first magnetic sheet differs from the coil component of FIG. 1 in that no hole is formed. The first and second magnetic sheets may be in contact with each other, but it is preferable to arrange the first magnetic sheet via a magnetic gap in the thickness direction so that the first magnetic sheet is not magnetically saturated with the magnetic flux from the magnetic attraction means. . Further, as described above, it is preferable to arrange the front surface of the magnetic attraction means so as to be the same height as the front surface of the coil. For this reason, it is preferable to use a magnetic attraction means that is thinner than the coil, and the magnetic attraction means should be a plate-like permanent magnet or a plate-like soft magnetic material that can be attracted to the magnet. preferable. However, the permanent magnet and the coating layer of the magnetic material may be included in the single body.

(Third embodiment)
FIG. 4 is a cross-sectional view of a coil component according to another embodiment.
With respect to the coil component of FIG. 1, the second magnetic sheet projects at least partly outward from the outer edge of the magnetic attraction means when viewed in the thickness direction. It is preferable that the second magnetic sheet is larger than the magnetic attraction means as a whole and protrudes from the entire outer edge like a collar of a hat. Shield performance can be improved.
In FIG. 4, the magnetic gap between the first magnetic sheet and the second magnetic sheet is intentionally widened so that the first magnetic sheet is not magnetically saturated. Specifically, the inner diameter of the first magnetic sheet is made larger than the inner diameter of the first magnetic sheet of the coil component shown in FIG. The inner diameter of the first magnetic sheet can be changed as appropriate.

(Fourth embodiment)
FIG. 5 is a cross-sectional view of a coil component according to another embodiment.
1 differs from the coil component of FIG. 1 in that the second magnetic sheet 1-2 has a refracting portion 5 formed so as to be folded into at least a part between the side surface of the coil 3 and the magnetic attraction means 2. The refracting portion 5 is preferably formed all around the magnetic attraction means 2. The second magnetic sheet can be formed by using a magnetic sheet larger than the magnetic attraction means 2 and refracting its end portion to form a refracting portion.
Since the refracting portion 5 has a function as a yoke material, it is possible to increase the magnetic attractive force acting between the power feeding device and the charging device. Moreover, it can suppress that the magnetic flux from a magnetic adsorption | suction means flows to the rear surface side of a coil, and will be in the state which a 1st magnetic sheet cannot carry out magnetic saturation easily. Therefore, since the fall of the magnetic permeability of a 1st magnetic sheet can be suppressed, the function as a yoke is fully acquired and the fall of electric power transmission efficiency can be suppressed as much as possible.
The height of the refracting portion 5 in the thickness direction is preferably such that the tip of the refracting portion is the same height as the front surface of the magnetic attraction means. Since the refracting portion covers the side surface of the magnetic adsorption means over a wide range, it is effective in suppressing saturation of the magnetic sheet, improving the shielding performance, and improving the magnetic attractive force of the magnetic adsorption means. When the magnetic attraction means and the second magnetic sheet are adjacent to each other, the height of the refracting portion is the same as the thickness of the coil. When another nonmagnetic material is interposed between the magnetic attracting means and the second magnetic sheet, the height of the refracting portion is preferably the sum of the thickness of the nonmagnetic material and the thickness of the magnetic attracting means. .

FIG. 6 shows an example of the power feeding device 20 used in the non-contact charging device.
The case 202 of the power feeding device 20 includes an upper case 202a and a lower case 202b made of a thin nonmagnetic resin plate. The upper surface of the upper case 202a constitutes a power feeding surface 203, and the back surface is flat. A magnetic attracting means 211 having a flat front surface at the center of the flat back surface of the upper case 202a, and a primary surface having a flat spiral spiral front surface surrounding the magnetic attracting means 211 coaxially (concentrically) via a magnetic gap. The coil 201 is fixed. Here, “coaxial” means that the central axis of the magnetic attraction means 211 and the central axis of the primary coil 201 coincide with each other, and when both are circular, they are concentric circles. The primary coil 201 is disposed as close as possible to the power feeding surface 203 in order to enhance electromagnetic coupling with a secondary coil 301 described later. By making the primary coil 201 a planar coil whose dimension (outer diameter dimension) in the direction perpendicular to the thickness dimension is larger than the thickness dimension, the magnetic circuit can be thinned, and the power feeding device can be reduced in height. The primary coil 201 may be molded with an insulating resin.

On the rear surface of the primary coil 201, a donut-plate-shaped first magnetic sheet having a size substantially covering the primary coil 201 (having an outer diameter larger than the outer diameter of the primary coil 201 and an inner diameter substantially the same as the inner diameter of the primary coil 201). 2121 is coaxially adjacent to prevent leakage of magnetic flux generated from the primary coil 201. The magnetic attraction means 211 is coaxially received in the central hole of the magnetic sheet 2121 through a magnetic gap when viewed in the thickness direction. The magnetic attraction means 211 is also arranged coaxially with respect to the magnetic sheet 2121. A second magnetic sheet 2122 is disposed on the rear surface of the magnetic adsorption unit 211 and shields the magnetic flux from leaking to the rear surface side.
A substrate 218 is fixed to the inner surface (upper surface in FIG. 11) of the lower case 202b. On a substrate 218 made of a dielectric, a coil terminal 27 to which a conductive wire end of the primary coil 201 is connected, a resonance capacitor 26, a rectifier circuit 22, a switching circuit 23, and the like are mounted.

  FIG. 7 shows an example of the power receiving device 30 used in the non-contact charging device. The case 302 of the power receiving device 30 includes a thin flat resin plate-like lower case 302a having a charging surface 303 that contacts the power feeding surface 203 of the power feeding device 20 during charging, and an upper case 302b having a liquid crystal display unit 39 and the like. Become. A magnetic attraction means 311 having a flat front surface at the center of the flat back side of the charging surface 303, and a secondary coil 301 having a flat spiral front surface surrounding the magnetic attraction means 311 coaxially through a magnetic gap. It is fixed. The secondary coil 301 is disposed near the charging surface 303 at a position facing the primary coil 201. The magnetic gap between the magnetic attraction unit 311 and the secondary coil 301 is preferably increased so that the secondary coil 301 is not substantially affected by the magnetic flux of the magnetic attraction unit 311. By using the secondary coil 301 as a planar coil, the magnetic circuit can be thinned, and the power feeding device can be reduced in height. The secondary coil 301 may be molded with an insulating resin.

  On the rear surface of the secondary coil 301, a donut plate having a size substantially covering the secondary coil 301 (having an outer diameter larger than the outer diameter of the secondary coil 301 and an inner diameter substantially equal to the inner diameter of the secondary coil 301). The first magnetic sheet 3121 having the shape is coaxially adjacent to prevent leakage of magnetic flux generated from the secondary coil 301. When viewed in the thickness direction, the magnetic attracting means 311 is coaxially received in the central hole of the first magnetic sheet 3121 through a magnetic gap. Therefore, the magnetic attracting means 311 is also arranged coaxially with respect to the first magnetic sheet 3121. A second magnetic sheet 3122 is disposed on the rear surface of the magnetic adsorption means 311 and shields the magnetic flux from leaking to the rear surface side.

  A substrate 318 is fixed to the back surface (upper surface in FIG. 7) of the upper case 302b. In addition to the coil terminal 37, the rectifier circuit 32, and the secondary battery 33 to which the conductive wire end portion of the secondary coil 301 is connected, a drive device (not shown) or the like is provided on the substrate 318 made of a dielectric as necessary. Has been implemented. The first magnetic sheet 3121 is preferably adjacent to the secondary coil 301 so that the magnetic flux generated from the secondary coil 301 does not leak. The substrate 318 and the first magnetic sheet 3121 may not be fixed.

  In any of the magnetic circuits of the power feeding device 20 and the power receiving device 30, the front surfaces of the magnetic attraction means 211 and 311 are preferably the same height as the front surfaces of the coils 201 and 301. That is, it is preferable that the magnetic attraction means 211 and 311 and the transmission coils 201 and 301 are disposed on the flat power feeding surface 203 and the back surface of the charging surface 303. The secondary coil 301 disposed on the front side is easily electromagnetically coupled to the primary coil 201, and high power transmission efficiency is obtained. Further, the magnetic attracting means 311 arranged on the front side has a large attracting force with respect to the magnetic attracting means 211 of the power feeding device 20, and positioning of the power feeding device 20 and the power receiving device 30 can be easily and accurately performed with a small permanent magnet. Therefore, the amount of magnetic flux leaking from the magnetic adsorption means 311 can be reduced. For this reason, the magnetic saturation range of the first magnetic sheet 3121 is reduced, the magnetic permeability of the first magnetic sheet 3121 is prevented from being lowered, and high power transmission efficiency is obtained.

  The number of turns of the primary coil 201 of the power feeding device 20 may be larger than the number of turns of the secondary coil 301 of the power receiving device 30. A primary coil 201 having a large number of turns can be used for the power feeding device 20 that is not required to be downsized as much as the power receiving device 30, and power is supplied to the secondary battery 33 in a short time with a voltage generated in the secondary coil 301 by the mutual dielectric action. Can be stored. The magnetic adsorption unit 211 may be the same as the magnetic adsorption unit 311 of the power receiving device 30.

  The magnetic sheet used for the coil component will be described. As the soft magnetic material used for the magnetic sheet, ferrite, a silicon steel plate, a metal ribbon manufactured by roll quenching, a composite material of these with a resin, and the like can be used. In order to reduce eddy current loss and improve charge transmission efficiency, it is preferable to make the soft magnetic material thinner. In this respect, a metal ribbon manufactured by roll quenching among the soft magnetic materials is particularly preferable. Specifically, a metal ribbon having a thickness of 50 μm or less made of an Fe-based amorphous material, a Co-based amorphous material, an Fe-based nanocrystalline material, a Co-based nanocrystalline material, or the like having a high saturation magnetic flux density may be used. The thickness of the metal ribbon is more preferably 30 μm or less, and further preferably 20 μm or less.

  As the magnetic sheet, a thin soft magnetic material may be used as it is, but it is preferably fixed to the reinforcing member in order to prevent breakage. Specifically, it is preferable to use a magnetic sheet obtained by laminating a metal ribbon with a resin sheet or the like. Only one magnetic sheet may be used, but a plurality of layers may be stacked via a resin sheet. The total thickness of all the soft magnetic materials used in the magnetic sheet can be 150 μm or less, and further 100 μm or less. It is also possible to constitute a thin one having a thickness of 50 μm or less.

  The magnetic attraction means 211 and 311 employ either (a) a permanent magnet and a magnetic yoke member made of a soft magnetic material, (b) only a permanent magnet or (c) only a magnetic yoke member. it can. As the magnetic yoke member, a plate-like shape or a cup-like shape can be appropriately changed.

  The coil component according to the present invention is not limited to the above-described power supply device and charging device for non-contact charging, and can be widely applied to electronic devices including a coil and a magnetic yoke, and a coil and a magnetic shield.

1-1: First magnetic sheet 1-2: Second magnetic sheet 2: Magnetic adsorption means 3: Coil 4: Secondary battery 5: Refraction unit 6: AC power supply 7: Circuit unit 8: Substrate 10: Coil component 20: Power supply device 30: Charging device

Claims (7)

A coil component comprising an annular coil, a first magnetic sheet opposed to one side in the thickness direction of the coil, and a magnetic adsorption means,
The first magnetic sheet has a hole formed in the central portion of the coil when viewed in the thickness direction,
The magnetic attraction means is disposed on the inner peripheral side of the coil via a magnetic gap in the in-plane direction and / or thickness direction of the first magnetic sheet with respect to the first magnetic sheet ,
Wherein on one side of the thickness direction of the magnetic attraction means is disposed a second magnetic sheet, said second magnetic sheet, at least a portion of projects outside the outer edge of the magnetic attraction means The coil component is arranged with respect to the first magnetic sheet via a magnetic gap in an in-plane direction and / or a thickness direction of the first magnetic sheet . 2. The coil component according to claim 1, wherein an end projecting outward of the second magnetic sheet is refracted and folded into at least a part between a side surface of the coil and the magnetic adsorption means. A coil component having a formed refracting portion. 3. The coil component according to claim 2 , wherein the magnetic attraction means has a flat front surface on the other side in the thickness direction of the coil, and the refracting portion has a tip at the same height as the front surface of the magnetic attraction means. A coil component, characterized by being formed so as to be. 4. The coil component according to claim 1, wherein a thickness of the magnetic attraction means is the same as or thinner than the coil. 5. 5. The coil component according to claim 1, wherein the front surface of the magnetic attraction means is disposed at the same height as the front surface of the coil. The power supply device characterized in that it comprises a coil component according to any one of claims 1-5. A charging device comprising the coil component according to any one of claims 1 to 5 .

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